This Packard Bell Legend 750 Supreme came from e-waste, and the first problem was simply figuring out what shape it was in. The case had the usual faded front plastic, but it still had the classic early 90s Packard Bell look with both 5.25-inch and 3.5-inch floppy drives on the front. Around back, most of the I/O was built into the motherboard, including serial, parallel, joystick, VGA, and PS/2, and it also had a built-in modem setup.
Once I opened it up, I found a couple of loose bags of parts rattling around inside the case. Those turned out to be SRAM chips for a cache upgrade along with the extra chip needed to complete it. The system had a Conner 170 MB hard drive installed, and under the modem card I found the CMOS battery tucked away in the corner. I expected leakage there, but this one had survived cleanly, so I removed the riser, crossbar, and modem to get the battery out and have a better look around the board.
The motherboard was a 486SX design with a socket for an optional math coprocessor, some onboard memory, four 32-pin expansion slots for more RAM, and empty sockets for L2 cache. I powered it up and it actually booted right away, although the hard drive was dead and making awful noises. The memory test passed and the machine came up to the BIOS without any trouble.
I paired it with a Packard Bell monitor, but that had its own issue. At first I only got green, then blue started to come in, and after warming up for a while all the colors returned. That one went on the list for a future recap. The computer itself was in much better shape than the display.
The 3.5-inch floppy drive wasn’t. I cleaned it, but it still wouldn’t read disks and kept making a nasty clicking sound, so I replaced it with a known good drive. That got me into DOS. The 5.25-inch drive was full of dust and grime, and at first it wouldn’t even accept a disk properly, so I cleaned it out, lubricated the rails and stepper shaft, and tested it with IMD.
That drive still failed, and the problem showed up clearly when I moved the heads back and forth in analyze mode. It would travel out cleanly, but on the return trip the stepper skipped and never made it all the way back to track zero. I set that drive aside as a bad stepper motor case and kept going with the working 3.5-inch drive.
With DOS running, I loaded Wolfenstein 3D to see how the machine felt. At first it was painfully slow, both loading and in gameplay, and then I remembered the turbo button. Once I turned turbo on and reloaded the game, it behaved like a 486 should and Wolfenstein ran fine through the PC speaker.
From there I installed the cache chips that had been left in the case. CacheChk initially showed only the 8K of internal L1 cache, and TopBench scored the machine at 71. After installing the SRAM, tag RAM, and dirty bit chip, CacheChk reported 256K of L2 cache, and TopBench went up to 76.
The Packard Bell ended up booting reliably, running DOS, and playing Wolfenstein 3D once the bad 3.5-inch drive was replaced and turbo was enabled. The 5.25-inch drive still needed a stepper motor repair, and the cache upgrade worked with a small benchmark bump.
— Aaron
Timestamps
00:00 – First Look
03:38 – Components
05:54 – PCBWay Ad
06:25 – First Boot
10:12 – Wolfenstein 3D
11:13 – Cache Upgrade
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